Next Article in Journal
The Dynamics of Changes in the Concentration of IgG against the S1 Subunit in Polish Healthcare Workers in the Period from 1 to 12 Months after Injection, Including Four COVID-19 Vaccines
Previous Article in Journal
Intranasal Coronavirus SARS-CoV-2 Immunization with Lipid Adjuvants Provides Systemic and Mucosal Immune Response against SARS-CoV-2 S1 Spike and Nucleocapsid Protein
Previous Article in Special Issue
Comparison of Bacterial Expression Systems Based on Potato Virus Y-like Particles for Vaccine Generation
 
 
Font Type:
Arial Georgia Verdana
Font Size:
Aa Aa Aa
Line Spacing:
Column Width:
Background:
Review

Efficacy and Immune Response Elicited by Gold Nanoparticle- Based Nanovaccines against Infectious Diseases

1
Division of Molecular Medicine and Virology, Department of Biomedical and Clinical Sciences, Linköping University, 58185 Linkoping, Sweden
2
King Abdulaziz City for Science and Technology (KACST), Riyadh 11442, Saudi Arabia
*
Author to whom correspondence should be addressed.
Vaccines 2022, 10(4), 505; https://doi.org/10.3390/vaccines10040505
Submission received: 17 January 2022 / Revised: 4 March 2022 / Accepted: 17 March 2022 / Published: 24 March 2022
(This article belongs to the Special Issue Virus-Like Particle and Nano-Particle Vaccines 2.0)

Abstract

:
The use of nanoparticles for developing vaccines has become a routine process for researchers and pharmaceutical companies. Gold nanoparticles (GNPs) are chemical inert, have low toxicity, and are easy to modify and functionalize, making them an attractive choice for nanovaccine development. GNPs are modified for diagnostics and detection of many pathogens. The biocompatibility and biodistribution properties of GNPs render them ideal for use in clinical settings. They have excellent immune modulatory and adjuvant properties. They have been used as the antigen carrier for the delivery system to a targeted site. Tagging them with antibodies can direct the drug or antigen-carrying GNPs to specific tissues or cells. The physicochemical properties of the GNP, together with its dynamic immune response based on its size, shape, surface charge, and optical properties, make it a suitable candidate for vaccine development. The clear outcome of modulating dendritic cells, T and B lymphocytes, which trigger cytokine release in the host, indicates GNPs’ efficiency in combating pathogens. The high titer of IgG and IgA antibody subtypes and their enhanced capacity to neutralize pathogens are reported in multiple studies on GNP-based vaccine development. The major focus of this review is to illustrate the role of GNPs in developing nanovaccines against multiple infectious agents, ranging from viruses to bacteria and parasites. Although the use of GNPs has its shortcomings and a low but detectable level of toxicity, their benefits warrant investing more thought and energy into the development of novel vaccine strategies.

1. Introduction

The development of vaccines and immunization programs against various kinds of diseases ranging from infections to cancer significantly progressed in the past few decades. One of the most important factors contributing to this growth is the advancement of nanotechnology. The use of nanoparticles in the development of vaccines is a major landmark step. One key step for the vaccine development process is the use of an optimal carrier or delivery system that can influence a potent immune response. The use of different types of nanoparticles and their roles in influencing the immune system has been studied in different disease models. Nanocarriers can be used as adjuvants in the preparation of new-age vaccines. The size, shape, route of administration, and antigen tagging mechanism on the nanoparticles are all critical in this [1,2]. In the past few years, major progress has been achieved in characterizing nanoparticle-based immunogenicity, immunotoxicity, the nature of immune suppression, and immunomodulation [3,4,5].
Among different nanoparticles already tried and used for the successful development of nanovaccines, the gold nanoparticle (GNP) is noteworthy. The chemical synthesis process of antigen tagging on the GNP and its formulations is easy, making it a suitable candidate in the nanovaccine manufacturing process [6]. Metallic nanoparticles such as GNPs provide a higher binding affinity, special electronic structures, plasmon excitation, and large surface energies owing to their higher surface area to volume ratio [7]. This also enables GNPs to interact with different functional groups or ligands with high affinity [8]. Due to its inherent magnetic and optical properties, colloidal gold has already been used in the treatment of a wide variety of diseases with a minimum level of cytotoxicity.
Multifunctional GNPs have been used by conjugating them with FDA-approved antimicrobial drugs and antibiotics in many studies [9,10,11,12,13,14,15]. GNPs coated with antigenic peptides have also been used to synthesize antibodies specific to the pathogens [16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,32]. The GNP-based drug or antigen delivery system is more competent for its controlled release to the target site [33]. GNP nanoformulations can be used by tagging specific antibodies or molecules to their surface. This enables efficient targeting to the particular cell types, leading to a site-specific immune response profile and less off-target distribution [34]. The GNP has by itself excellent adjuvant properties to boost the immune system of the host. The variations in size, shape, charge, and surface functionalization are all crucial in eliciting varied immune responses upon administration [35]. Some of these properties are highlighted in Figure 1.
One key concern regarding the use of any foreign chemical such as gold in any form of treatment intervention is its possible harmful side effects. However, the administration of gold as an adjuvant or in a nanovaccine formulation has a high safety profile with few side effects [36,37]. Like any other nanomaterial, GNPs also have certain limitations that we discuss later in this review. However, the advantages of using them for new-age vaccine development are showing promising results and far surpassing the concern.
Although GNPs are widely used in the development of vaccines against multiple cancers, in this review, we focus on their use in vaccination against infectious agents. We discuss the characteristic features of gold nanoparticles that make them advantageous to use in vaccine development, including their shape, size, and generated immune response (Figure 2). We specifically elaborate in separate sections about the use of gold nanovaccines in different types of immune cells and infections: bacterial, viral, and parasitic. We highlight the advancements made in the use of gold nanoparticles in the vaccine development process.

2. GNP Characteristics and Features Make It Indispensable in Vaccine Development Research

GNPs are often used to develop a potent antigen carrier system for immunization [1,2,33,34,35,36,37]. They are easy to prepare and have special physicochemical properties with very little toxicity [38]. Multiple variables in the shape, size, geometry, and surface modifications influence GNP function. The stability of the GNP and its flexibility helps in manufacturing GNPs with variable core diameter, size, and shape. Conversion of the electromagnetic radiation to heat by this noble metal can be exploited for therapeutic and targeting purposes [39,40,41,42]. However, there is no relevant systemic study for an optimal and standard GNP system for all applications [41,42].
Precision in the nanocarrier delivery and penetration to the site of interest or the immune cells is a critical component. This facilitates the induction of the immune response genes, antigen processing, cytokine production, antibody secretion, and T cell stimulation for effective therapy or vaccine efficacy [43,44,45,46]. GNPs have unique size and surface area properties. They can penetrate blood vessels and tissue barriers and can deliver to targeted sites due to their high uptake efficiency [37,47,48].
GNPs are efficient in delivering antigens into the major antigen-presenting cells such as dendritic cells, facilitating the downstream immune response, cross-presentation, and CD8+ cytotoxic T cell response (Figure 2A,B) [49]. Along with passive targeting by varying the size and shape of the GNPs to make them more prone to internalization by the individual cell types, active targeting can also be achieved via surface modifications and functionalization. For example, using GNPs coated with antibodies for DEC205, CD40, CD11c, or mannose can be selectively uptaken by dendritic cells by the process of receptor-mediated endocytosis [50,51,52]. For targeting them to macrophages, CD44, folates, and lectins are used [53,54,55]. Thus, loading GNPs with immune target antibodies leads to the activation and stimulation of the specific immune cells.
GNPs are biocompatible and inert. They are easily functionalized with a wide range of peptides and molecules and are also very stable [2,56,57,58,59]. GNPs can be packaged inside virus-like particles (VLP) using the expression of structural genes of the virus and can be used in the vaccine development process [60]. GNPs can be conjugated with the polysaccharide or protein linkers before their antigenic functionalization. The immunomodulating capacity of gold glyconanoparticles is well known. In many vaccine development programs, the GNP is used as an adjuvant to stimulate the immune response [61,62]. Hence, all these features make the GNP a favored choice in biomedical applications for vaccination, drug delivery, and tracking (Figure 1).
The GNP shape, size, charge, and conjugated materials all influence organ accumulation and blood clearance [63]. Progress has been made to optimize GNP pharmacokinetics by increasing the half-life time of its circulation and its physical size and by reducing the mononuclear phagocytosis system (MPS)-based clearance [64]. Polyethylene glycol (PEG)-mediated surface modification of GNPs is commonly used to decrease MPS activity and increase their circulatory half-life [65]. Using 15 nm GNPs provides a better half-life than 100 nm GNPs, while GNPs smaller than 6 nm are rapidly filtered out by the kidneys [66,67]. Protein crown formation on the GNP after its entry into circulation and opsonization facilitate its recognition by MPS of liver, spleen, and marrow, leading to its higher accumulation in these organs [68]. This crown formation also has a crucial impact on biodistribution, as it masks the original functionalization of the GNP [69,70].

3. Shape and Size of GNP Influence Its Impact on the Immune System

The size of the GNP, along with its shape, influences the immune system differently. This shape and size dependency of the adjuvant activity of GNPs is used to polarize the immune response in different scenarios to deliver the best outcome [37,38,39,40,41,42].
Rod-shaped GNP-treated bone marrow dendritic cells (BMDCs) produce high levels of IL1b and IL18, whereas cube- and spherical-shaped GNPs result in the production of high levels of pro-inflammatory cytokines such as tumor necrosis factor-alpha (TNFa), interleukin (IL)-6, IL17, and granulocyte-macrophage colony-stimulating factor (GM-CSF) [71]. Niikura et al. [72] studied the varieties of GNP shapes: spherical, rod, and cube. This group found that the ratio between the total surface area per single nanoparticle volume is critical for antibody response and TNFa production. They found that larger-sized (40 nm) spherical GNPs are more efficient in producing IL6, IL12, and GM-CSF than the smaller-sized or differently shaped GNPs [72]. GNP functionalization by chemical modification, addition or removal of functional group, antigen coating, etc., influences surface charge and hydrophobicity, leading to alterations in the level of immune response thus generated (Figure 2) [73,74].
Chen et al. studied the impact of GNP sizes spanning from 2 to 50 nm and found that those between 8 and 12 nm are mostly drained nanoparticles [18]. GNPs between 14 and 20 nm are reported to be better uptaken by the cells. An increase in the diameter leads to more toxicity. Receptor-mediated endocytosis may be the probable mechanism by which GNPs enter the cells [50,51,52,75]. The diameter of a GNP is also correlated with its localization inside the cell. A tiny GNP with a diameter of around 2.4 nm can be localized inside the nucleus, whereas a particle size of around 5.5 to 8.2 nm is found mostly in the cytoplasm. The nanoparticles with a higher diameter above 18–20 nm do not generally enter the cells [39,40,41,42,76].

4. Effect of GNPs on Dendritic Cells, Macrophages, and Natural Killer Cells

4.1. Dendritic Cells

The effect of GNPs on DCs is critical as it can activate the branch of the adaptive immune system. GNPs surface-tagged with DC-targeting molecules results in the better induction and polarization of immune response (Figure 2A,B) [77]. Although many studies [78,79] suggest the possible cytotoxicity, phenotype alteration, cytokine production, and activation by GNPs targeting DCs, the intricate details of such interaction, stimulation, or suppression of the immune system are yet to be divulged. In one study, DCs loaded with a GNP-conjugated Listeria antigen were adoptively transferred to naïve animals, leading to the induction of natural killer cells, CD8 + T cells, and better Th1 response and vaccine efficacy than any other traditional immunization methods [24].
DC from bone marrow, when stimulated by GNP, starts producing IL6, TNF-α, and interferon gamma (IFN-γ) [80]. GNP can induce the extracellular traps for the neutrophils, leading to immune system triggering via DNA receptors such as Toll-like receptor 9 (TLR9) [81]. GNPs coated with polyethylene glycol (PEG) or polyvinyl alcohol (PVA) or both increased their interaction with monocyte-derived dendritic cells (MDDCs). Although PEG coating restricts GNP uptake, it enhances the TNFa synthesis. PVA- or PEG+PVA-coated GNPs have a higher rate of uptaking with IL1b synthesis, although both types of coating do not influence the immunological characteristics, phenotypes, or activation of MDDCs [82].

4.2. Macrophages

The polarization and function of macrophages are reported to play a key role in different disease conditions [83]. GNPs are reported to promote crosstalk between the macrophages and other cells for tissue regeneration [84] and also suppress pro-inflammatory cytokine release from the macrophages. Similar suppression of immune response is reported in the lipopolysaccharide (LPS)-treated splenocytes in the presence of GNPs [85,86].
GNPs are reported to have oxygen radical scavenging properties in the mouse macrophages as they reduce the reactive oxygen species (ROS) of GNPs in a dose-dependent manner in the presence of LPS treatment [24]. The reduction in the pro-inflammatory cytokines, including IL17 and TNFa, is also noteworthy in the same set of experiments [87].

4.3. Natural Killer Cells

Natural killer cells (NK) sourced from the lymphoid progenitor lineage play a crucial role in immune surveillance in the circulation. They release granzymes and perforins to induce infected cell lysis. GNPs have been researched to target NK cells by using the mechanism of NK cell-mediated antibody-dependent cellular cytotoxicity (ADCC). This is the use and targeting of the NK cell receptors by antibody-tagged GNPs. This helps in the delivery and activation of NK cells [87].
PEGylated polyamidoamine dendrimers entrapped within GNPs to transfect human ferritin heavy chain in the NK cells constitute a novel immunotherapy method [88]. A modified version of GNPs has an anti-inflammatory response while being used to treat NK cells in vitro, significantly reducing IFN-γ secretion [89].

5. Use of GNP in Antiviral Immunization

GNP is a favored tool of virologists and has been used frequently in the development of the antiviral vaccination process.

5.1. HIV

Human immunodeficiency virus (HIV) possesses an important cluster of mannose-rich glycans in its envelope glycoprotein called gp120, which is recognized by 2G12-like antibodies. Gold nanoparticles were synthesized with a monolayer coating of self-assembled oligomannosides (similar to gp120) and were capable of binding with 2G12 [90]. GNPs attached with thiol-terminated oligosaccharides have also been used for developing HIV vaccines [91].
GNPs 2 nm in size coated with a synthetically prepared partial structure of multiple mannosidases [91,92] provide excellent binding to anti-HIV antibody-like 2G12. The third variable region (V3 peptide) of gp120 of HIV1 forms alpha helix or beta-strand conformation, which can be conjugated to GNP. This makes them more stable against any form of peptidase degradation and can also produce a high amount of specific neutralizing antibodies in rabbits [92].
Rabbits were immunized intramuscularly with 50 μg of 2 nm glyconanoparticles coated with the V3β peptide of the HIV-1 gp120 protein. Post-immunization, they produced a high titer of neutralizing antibodies against HIV1 [91,93]. Moreover, Gag p17 peptide of HIV1 conjugated with 2 nm GNP exhibited an increased proliferation of cytotoxic and helper T cells specifically against HIV, along with functional IL-1β and TNF-α cytokine production [93]. GNPs conjugated with Gp120, and gp41 HIV proteins have also been tested for vaccine development.

5.2. Hepatitis B

Hepatitis B virus surface antigen (HBsAg) DNA coated with GNP was injected into the epidermic cells employing a gene gun as a possible treatment measure [94]. GNPs were also used as adjuvants along with plasmid DNA encoding HBsAg DNA and injected into mice. The presence of GNPs triggers fast antibody production that leads to a quick achievement of the peak antibody titer in the animals [95].
In vitro studies in RAW 264.7 macrophages with a gold nanocage conjugated with HBsAg showed better uptake and antigen processing with IL4 secretion [96]. Recent advances have been made in the detection and diagnosis of the HBsAg by using GNP [97,98].
Virus-like particles (VLP) were produced with 10 nm GNPs conjugated with CpG oligodeoxynucleotides (ODN) and core antigen of hepatitis B. Mice immunized four times with 50 μg conjugate (i.p.) showed a 200% increase in the antibody titer as compared to GNP-free administration. CD4 helper T cells and CD8 cytotoxic T cell population expanded with the higher secretion of IL-4 and IFN-γ, along with immunostimulation of both Th1 and Th2 responses [62].

5.3. Hepatitis C

An interesting and effective means of delivery of hepatitis C virus DNA vaccine was proposed by a group that used plasmonic GNP activated by an electrical charge. This led to increased pore formation on the cell membrane and enhanced uptake of the DNA vaccine. The immunized mice group exhibited 100 times more gene expression as compared to the control group (without GNP use), with highly activated humoral and cell-mediated immunity being reported [99]. E2 proteins of hepatitis C were used to conjugate with GNP and immunize the mice to obtain higher igG production and proliferation of splenocytes [100].

5.4. Dengue

GNPs 20, 40, and 80 nm in size were used to conjugate the serotype 2-derived domain III envelope glycoprotein of dengue virus (EDIII). The conjugate administered three times subcutaneously to BALB/C mice led to the production of serotype-specific concentrated neutralizing antibodies. The size and concentration of GNPs were manipulated to affect the levels of antibodies produced in the animals. Splenocyte proliferation, helper, and cytotoxic T cell expansion and activation with the increased synthesis of IL-4 and IFN-γ were observed in mice [16]. GNP was also conjugated with small interfering RNA (siRNA) produced against the dengue virus. GNP in this conjugation helped in the enhanced stability and delivery of siRNA and elicited a better immune response [101].

5.5. Influenza

Much work on the development of a vaccine against influenza by using the GNP has been carried out by Gill’s group. They took a highly conserved N-terminal conserved extracellular domain of influenza virus matrix protein 2 (M2e) peptide and conjugated it with a 12 nm GNP [102,103]. They used soluble CpG and CpG ODN as their adjuvants. BALB/C mice were immunized two times with the conjugates, which led to enhanced production of IgG1 and IgG2 and better protection against a lethal dose of PR8-H1N1 infection challenge [104].
Another group has shown that even after 15 months of vaccination with GNP/M2e+ CpG conjugate, the mice retained M2e-specific neutralizing antibody production and could survive the lethal H1N1 challenge. They suggested that the vaccinated mice could effectively retain the memory B cells specific to the M2e peptide used [105].
Two intraperitoneal doses of M1 antigen of influenza virus conjugated with 15 nm GNP led to a higher titer of neutralizing antibody production along with the synthesis of IFN-γ and interleukins (ILs) 1β and 6. The activation of spleen lymphocytes and peritoneal macrophage respiration was also reported [106].
Another study proposed the use of more than one antigen against influenza in the same vaccination dose. They prepared and administered GNPs conjugated with hemagglutinin and flagellin of the H3N2 influenza virus. This vaccination process generated stronger systemic and mucosal immunity and better protected the animals from the lethal influenza challenge, compared to when a single antigen conjugate was used [107,108].
Many other vaccination processes have been developed against viral pathogens. A few of them are highlighted in Table 1.
Table 1 some of the studies focusing on the use of GNP-based nanovaccines against viral pathogens. Surface proteins from the viruses are tagged on the GNP to develop the nanovaccines. Most of the studies focus on mice models for demonstrating immune activity. The key factor of these studies is the successful development of the antibodies with neutralizing capacity [114]. Although one study reports the effectiveness of their novel GNP vaccine to be superior to the commercially available one [109], many other studies lack this important criterion to investigate. Enhanced activity by the professional antigen-presenting cells, such as dendritic cells and macrophages, is reported [110,111,112,114].
Expert opinion and future perspectives on Section 5 and Table 1: Most of the studies regarding the antiviral use of GNP-based vaccination programs focus mostly on the humoral or antibody-based immune protection by the host. Antibody titers are taken as the primary consideration to evaluate the efficacy of the novel immunization program. The cell-mediated immunity and particularly the maturation differentiation activation status of the dendritic cells, T cell subtypes, etc. (Figure 2B,C), are not studied in detail in many of these studies. Studying in depth this branch of immunity might answer various questions that are yet to be addressed.
Apart from the GNP-based influenza vaccine development (Section 5.5.), most other studies have not explored the possibility of the use of multiple protein epitopes of the pathogens conjugated to the GNP surface. Studying that aspect might expand the possibility of conferring a broad protective immunity against the pathogen. Future studies of isolating the memory cells (Figure 2D) from the vaccinated host and transferring them to naïve animals might be interesting for exploring the possibility of long-term immune protection. The comparative profiles of the routes of administration of the novel GNP-based vaccines are not disclosed or presented in most of these studies. Each study has shown either subcutaneous or intramuscular or intraperitoneal mode of delivery. The question remains on the possibility of a better immune response by the host if the vaccine is delivered through other delivery routes.

6. Use of GNP in Antibacterial Immunization

GNP is used for designing and delivering antigens for immunization in a number of bacterial infections. In some cases, it also acts as an adjuvant. Antigenic fragments from bacterial sources are tagged along with the GNP to stimulate the immune response generated against them.
A vaccine against the N terminal domain of the flagellin subunit of Pseudomonas aeruginosa along with GNP and Freund’s adjuvant induces a better IgG response [23]. Two antigens from Francisella tularensis were isolated and conjugated with 15 nm GNP to immunize the animals and obtain antitularemia sera rich in neutralizing antibodies [115]. In another study, 15 nm GNP was used as the adjuvant for the first time during the preparation of antibodies against the surface of the antigens of Yersinia pseudotuberculosis [116].
Another group studied the efficacy of the antibodies raised against F1 antigens of Y. pestis after coating it on 15 nm GNP. It helped elicit igG2a levels, interferon gamma, and Th1 cell activation [21]. Similarly, synthesized surface antigens of Salmonella typhimurium were also coated on GNPs and were reported to have better immunogenic properties in the clearance of the bacteria [117]. Non-immunoactive mono- and disaccharides derived from capsular polysaccharides of Neisseria meningitidis were coated on GNP and reported to have better T cell activity, MHCII presentation, and immune properties [118].
Several other uses of GNPs in the immunization process against bacterial infection are discussed in Table 2.
Table 2 some of the studies focusing on the use of GNP-based nanovaccines against bacterial pathogens. Successful production of neutralizing antibodies is the key to combating pathogens. These studies demonstrate that the GNP-based nanovaccine formulation can successfully combat these bacteria. The use of adjuvants makes the nanoformulations perform better [26,121,122,123]. The activation of the T cell subsets in most of these studies is an indicator of dual combating potential by means of cell-mediated and humoral-mediated immunity. It is interesting to note that there is only a minor difference in the immune response based on the route of administration. Some studies use more than one route of vaccine delivery [24,119,121,122,123]. The cytokine response is inclined to a pro-inflammatory or Th1 immune response [19,121,122,123], creating ideal conditions for the clearing of the pathogens.
Expert opinion and future perspectives on Section 6 and Table 2: It is more common to take vaccines against the virus than bacterial pathogens. Although most of the studies here show promising results for the use of vaccines against multiple types of bacteria, it is not yet clear how the host benefits from the antibacterial vaccines in comparison to the available antibiotics. It would be relevant to compare the controlled drug release via GNPs in the infectious site with that established in many GNP-based cancer vaccination programs. Many FDA-approved drugs and antibiotics are used to conjugate with GNP for various treatment possibilities. Some of these antibiotics are Ciprofloxacin [9], Lincomycin [10], Vancomycin [11], Ampicillin [12], Cefaclor [13], Rifampicin [14], and Kanamycin [15].
Most of the animal studies discussed in Section 6 and Table 2 did not follow up with the host for a considerable period after the vaccination. Thus, the duration and the strength of the immune protection conferred by these vaccines remain unclear. Gold nanoparticles are reported to have adjuvant properties for boosting the immune system. It would be interesting to study what proportion of the host immune protection is derived from the GNP alone as compared to the combination of other adjuvants used in these studies. In Table 2, most of the GNPs used range from 15 to 25 nm in size. As it is already well known that the size of the GNP influences the immune response, it would be useful to study the comparative account of the use of differently sized GNP in these studies.

7. Use of GNP in Anti-Parasitic Immunization

Some parasitic infections are being studied where GNP plays a critical role in generating the immune response in the host to combat the infections. The following table describes a few of them.
Table 3 some of the studies focusing on the use of GNP-based nanovaccines against parasitic pathogens. The activation of both MHC I and II was reported, along with both the CD4T and CD8T response [124]. These are the keys to fighting against pathogens. The high titers of specific antibodies [31,32] with better host responses against the pathogens were observed.
Expert opinion and future perspectives on Section 7 and Table 3: The studies aiming at GNP-based vaccination in parasitic diseases are relatively few, and there are various scopes to improve and explore. Plasmodium falciparum is one key pathogen mostly studied by various groups because of its wide prevalence and potential to cause deaths worldwide.
In the previous three sections of this review, we discussed the successful laboratory implementation of GNP-based nanovaccines. It would be interesting to explore and carry out a comparative study of treatment with the antibody synthesized by using GNP-conjugated antigens side-by-side with the GNP nanovaccine formulations to determine which treatment works best in a particular infection. GNPs conjugated with the antigens, haptens, and adjuvants (such as Freund’s or alum) of various pathogens have been used to obtain the antibodies. Some of these pathogens are dengue viruses [16], foot-and-mouth disease [17,18], influenza [19], Escherichia coli [20], Yersinia [21], tetanus toxoid [22], Pseudomonas aeruginosa flagellin [23], Listeria monocytogenes [24], Streptococcus pneumoniae [25], Burkholderia mallei [26,27], Neisseria meningitides [28], tuberculin [29,30], and malaria plasmodium surface proteins [31,32].

8. Limitations of the GNP

The use of the GNP shows some promising results in nanovaccine development technology. Still, it is not free from limitations. GNP, being a non-biodegradable agent, can easily be accumulated in vivo, which eventually might lead to certain side effects. Such non-porous and non-biodegradable properties might impair GNPs’ impact on the encapsulation and the timed or targeted release.
Biosafety is a major concern when using any nanomaterial. A research group has shown that encapsulated GNP conjugated with fluorescein isothiocyanate (FITC) suppresses reactive oxygen species and cytokine secretion from the macrophages [125]. GNP size-dependent toxicity is reported with smaller diameters (1–2 nm) that can be internalized by cells and organelles such as nuclei and mitochondria, leading to the induction of irreversible cellular damage [126,127]. GNPs more than 15 nm in diameter are mostly localized to the cytoplasm without being uptaken by the organelles [127]. Meanwhile, 20 nm GNPs cause oxidative stress, activate the autophagic pathway, and finally lead to genomic instability [128]. Other groups have shown lysosome impairment [129] and higher mitochondria [130], endoplasmic reticulum, and Golgi apparatus [131] accumulation of GNPs within the cell. Thus, we can see reports of the disruption of cellular metabolism due to the accumulation of GNPs in cells and their organelles.
The low penetration depth of GNPs due to the photothermal effect is a limiting factor to release the drugs or vaccinating agents into the depth required, leading to lessened immunoregulatory activities [132]. Surface modifications on the GNPs can lead to the alteration of the histocompatibility and pharmacokinetic parameters [133]. Thus, each variant of the GNP must be characterized individually before being used in therapeutic or clinical settings.
Moreover, there is still a lack of in-depth understanding about GNPs’ influence upon interaction with different cell types, especially after the modifications. Although reports suggest the formation of reactive oxygen species (ROS), oxidative stress and cell cycle impacts with induced DNA damage are also possible biological cellular responses [134,135,136,137]. GNPs coated with 1.4 nm triphenyl monosulfonate induced oxidative stress within the cells, with mitochondrial potential loss leading to necrosis [138]. The endogenous redox capacity of the cells was also impaired by GNPs by depleting the naturally available antioxidants in the cells [138].
Positively charged GNPs are reported to have a more toxic effect due to their propensity toward negatively charged DNA and cell membranes. However, both positively and negatively charged GNPs, and not neutrally charged, have been reported to have harmful impacts leading to mitochondrial stress [139,140].

9. Discussion and Future Perspectives

In this review, we discussed the promising potential of the gold nanoparticle for prophylactic and therapeutic purposes. Advancements in the field of nanotechnology coupled with vaccine research have paved the way for successful nanovaccine development for combating many deadly infections. Being relatively safe to administer in humans, GNPs are widely used in the development of vaccines for many diseases, ranging from cancer to infections. Some of the vaccines developed against different cancer forms are in clinical trials and show promising outcomes. The summarized advantages and limitations of the GNP in its use in the vaccine development process are tabulated in Box 1.
Box 1. Advantages and limitations of the use of GNPs in the vaccine development process.
Advantages
  • Biocompatible
  • Easy synthesis process
  • Size- and shape-dependent varied immune response
  • Colloidal stability
  • Optical properties
  • Efficiency in molecule loading on the surface
  • Surface functionalization flexibility and multi functionalization property
  • Can be designed for targeted delivery and controlled release of drugs
  • Photothermal conversion potential
  • Inherent adjuvant potential
  • Usage in imaging techniques
  • High binding affinity with wide range of molecules
  • Higher surface area to volume ratio
  • Large surface energy and charge
Disadvantages/Limitations
  • Non-biodegradable
  • Non-porous
  • Limited penetration depth
  • Altered biodistribution profile upon surface modification
  • Surface functionalization-mediated toxicity and pharmacokinetics issues
  • Limited knowledge of impact on multiple cell types
  • Clearance by macrophage phagocytosis system and renal pathway
  • Accumulation in cellular organelles such as mitochondria, lysosomes, etc., hampering normal cellular metabolism and ROS production
The properties of gold nanoparticles and the ease of their usage and functionalization make them attractive to researchers. Attaching the isotopes or fluorochrome tags or optical probes with gold nanoparticles and targeting them to specific cells by attaching the antibodies or targeting ligands remarkably helped the advancement of optical imaging techniques, as well. Another success of using GNPs has been achieved in obtaining the antibodies for immunological identification of different pathogens in biosensor or microscopic methods. GNP antigen-conjugated vaccines are reported to protect animals from a lethal dose of virulent challenge with a 100% survival rate [140].
There are certain concerns regarding the role of GNPs in the inhibition of Th1 response, which is crucial in combating many pathogenic infections. Only one study reported the enhancement of Th1 as well as Th17 immune response; the authors used the Listeria antigen along with the combination of Advax and 25 nm GNP adjuvants [24]. Most of the other studies highlight the increase in the Th2 response post-GNP administration. However, this shortcoming inactivation of the proinflammation by the GNPs themselves is overcome mostly by the antigens or drugs they are carrying or the cells they are targeting via the attached ligands.
To improve prospects regarding the use of GNPs in vaccine development and in clinical settings, there is a pressing need to address certain issues. Firstly, there must be a large-scale production setup for GNPs with a high level of consistency. As we have addressed before, multiple variable factors such as charge, size, and shape all impact the cells in different ways. Thus, we need to be clear and cautious about each change that we are implementing. We have also noticed that most labs are working with GNP sizes ranging from 15 to 50 nm. Moreover, nanoshell-structured GNPs are most often used rather than other shapes such as nanocage, nanorods, nanocubes, etc. Therefore, we lack knowledge of the GNPs sized or shaped differently than as mentioned.
Secondly, it is important to characterize with better clarity the GNPs’ impact upon interaction with immune cells. We believe a detailed investigation of immune cells in the presence of functionalized or empty GNPs will be helpful for answering various questions. Third, the biodistribution of the GNP must be evaluated in further detail, with special emphasis on the off-target cells and organs. Most studies highlight only the organs or cells or the disease pathogen and do not consider the possible accumulation of the nanomaterial in other organs. This leads to our fourth concern: nanotoxicology. As already discussed, the GNP is a non-biodegradable substance; thus, there may be a need to develop a synthesis or tagging method that can make it less toxic or better suited for clearance.
Fifth, the protein coating formed outside the GNP surface upon in vivo introduction (also known as bio-corona) is a problematic factor for the efficacy of the conjugated antigens on its surface. This bio-corona formation blocks the coating antigens and materials from interacting with in vivo cellular physiology. Sixth, as there is no specific dosage yet, the problem remains of replicating the success observed in animal experiments in early clinical trials. The standardization and normalization of the dose must be established.
Seventh, a key important issue that needs to be addressed is how to fashion the GNP so that it can evade clearance by MPS or by renal excretion before its intended action. Studies have suggested coating GNPs with PEG, polyvinyl alcohol, poly (acrylic acid), or biomolecules such as glutathione or albumin to prevent bio-corona formation and MPS-based clearance and provide stability with relative less off-target toxicity [64,141,142]. Eighth, as the use of gold always bears a cost, logistical concerns regarding the manufacture and distribution of such vaccines across a wide range of populations must be considered.
Future work should address the impact of the combination strategies with GNP-based delivery along with photothermal therapy. It would also be interesting to explore the optical properties of GNPs in combination with thermal therapy in inflammatory responses. We expect that although some of the GNP-based nanoformulations discussed in this review might be translated into clinical settings, it is vital to address the multiple challenges associated with GNPs. Therefore, of paramount importance are the balanced testing and validation of their safety before establishing them in biomedical applications.

Author Contributions

Conceptualization, A.S., M.A., J.H. and N.A.-O.; Methodology, A.S., J.H. and M.A.; Validation, A.S., J.H., M.A. and N.A.-O.; Writing—original draft preparation, A.S. and M.A.; Writing—review and editing, A.S., M.A., J.H. and N.A.-O. All authors have read and agreed to the published version of the manuscript.

Funding

This work was supported by The KACST fund: KING ABDULAZIZ CITY FOR SCIENCE AND TECHNOLOGY “KACST” Dnr: ETS-LiU-2020-02-11. MIIC stipend fund 2021-06.

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

Upon request we can, within a reasonable timeframe, provide data described in this manuscript.

Conflicts of Interest

The authors declare no conflict of interest. The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

References

  1. Comber, J.D.; Bamezai, A. Gold nanoparticles (GnPs): A new frontier in vaccine delivery. J. Nanomedine Biother. Discov. 2015, 5, 4. [Google Scholar]
  2. Salazar-González, J.A.; González-Ortega, O.; Rosales-Mendoza, S. Gold nanoparticles and vaccine development. Expert Rev. Vaccines 2015, 14, 1197–1211. [Google Scholar] [PubMed]
  3. Fadeel, B. Hide and seek: Nanomaterial interactions with the immune system. Front. Immunol. 2019, 10, 133. [Google Scholar]
  4. Frey, M.; Bobbala, S.; Karabin, N.; Scott, E. Influences of nanocarrier morphology on therapeutic immunomodulation. Nano-Med. 2018, 13, 1795–1811. [Google Scholar]
  5. Kelly, H.G.; Kent, S.J.; Wheatley, A.K. Immunological basis for enhanced immunity of nanoparticle vaccines. Expert Rev. Vac.-Cines 2019, 18, 269–280. [Google Scholar]
  6. Fai, T.K.; Kumar, P.V. Revolution in the Synthesis, Physio-chemical and Biological Characterization of Gold Nanoplatform. Curr. Pharm. Des. 2021, 27, 2482–2504. [Google Scholar] [CrossRef] [PubMed]
  7. Personick, M.; Langille, M.R.; Zhang, J.; Mirkin, C.A. Shape Control of Gold Nanoparticles by Silver Underpotential Deposition. Nano Lett. 2011, 11, 3394–3398. [Google Scholar] [PubMed]
  8. Rescignano, N.; Kenny, J.M. Stimuli-Responsive Core-Shell Nanoparticles; Elsevier: Amsterdam, The Netherlands, 2018. [Google Scholar]
  9. Rosemary, M.J.; MacLaren, I.; Pradeep, T. Investigations of the Antibacterial Properties of Ciprofloxacin@SiO2. Langmuir 2006, 22, 10125–10129. [Google Scholar] [CrossRef]
  10. Shittu, K.O.; Bankole, M.T.; Abdulkareem, A.S.; Abubakre, O.K.; Ubaka, A.U. Application of gold nanoparticles for improved drug efficiency. Adv. Nat. Sci. Nano Sci. Nanotechnol. 2017, 8, 035014. [Google Scholar] [CrossRef]
  11. Roshmi, T.; Soumya, K.R.; Jyothis, M.; Radhakrishnan, E.K. Effect of biofabricated gold nanoparticle-based antibiotic conjugates on minimum inhibitory concentration of bacterial isolates of clinical origin. Gold Bull. 2015, 48, 63–71. [Google Scholar] [CrossRef] [Green Version]
  12. Fan, Y.; Pauer, A.C.; Gonzales, A.A.; Fenniri, H. Enhanced antibiotic activity of ampicillin conjugated to gold nanoparticles on PEGylated rosette nanotubes. Int. J. Nano Med. 2019, 14, 7281–7289. [Google Scholar] [CrossRef] [Green Version]
  13. Rai, A.; Prabhune, A.; Perry, C.C. Antibiotic mediated synthesis of gold nanoparticles with potent antimicrobial activity and their application in antimicrobial coatings. J. Mater. Chem. 2010, 20, 6789–6798. [Google Scholar] [CrossRef] [Green Version]
  14. Gajendiran, M.; Yousuf, S.M.J.; Elangovan, V.; Balasubramanian, S. Gold nanoparticle conjugated PLGA–PEG–SA–PEG–PLGA multiblock copolymer nanoparticles: Synthesis, characterization, in vivo release of rifampicin. J. Mater. Chem. B 2013, 2, 418–427. [Google Scholar] [CrossRef] [PubMed]
  15. Payne, J.; Waghwani, H.K.; Connor, M.; Hamilton, W.; Tockstein, S.; Moolani, H.; Chavda, F.; Badwaik, V.; Lawrenz, M.B.; Dakshinamurthy, R. Novel Synthesis of Kanamycin Conjugated Gold Nanoparticles with Potent Antibacterial Activity. Front. Microbiol. 2016, 7, 607. [Google Scholar] [CrossRef] [PubMed]
  16. Quach, Q.H.; Ang, S.K.; Chu, J.-H.J.; Kah, J.C.Y. Size-dependent neutralizing activity of gold nanoparticle-based subunit vaccine against dengue virus. Acta Biomater. 2018, 78, 224–235. [Google Scholar]
  17. Dykman, L.A.; Staroverov, S.; Mezhennyj, P.; Fomin, A.S.; Kozlov, S.; Volkov, A.; Laskavy, V.N.; Shchyogolev, S.Y. Use of a synthetic foot-and-mouth disease virus peptide conjugated to gold nanoparticles for enhancing immunological response. Gold Bull. 2015, 48, 93–101. [Google Scholar] [CrossRef] [Green Version]
  18. Chen, Y.-S.; Hung, Y.-C.; Lin, W.-H.; Huang, G.S. Assessment of gold nanoparticles as a size-dependent vaccine carrier for enhancing the antibody response against synthetic foot-and-mouth disease virus peptide. Nanotechnology 2010, 21, 195101. [Google Scholar] [CrossRef] [Green Version]
  19. Gao, W.; Fang, R.H.; Thamphiwatana, S.; Luk, B.T.; Li, J.; Angsantikul, P.; Zhang, Q.; Hu, C.-M.J.; Zhang, L. Modulating Antibacterial Immunity via Bacterial Membrane-Coated Nanoparticles. Nano Lett. 2015, 15, 1403–1409. [Google Scholar] [CrossRef] [Green Version]
  20. Sanchez-Villamil, J.I.; Tapia, D.; Torres, A.G. Development of a Gold Nanoparticle Vaccine against Enterohemorrhagic Esch-erichia coli O157:H7. mBio 2019, 10, e01869-19. [Google Scholar] [CrossRef] [Green Version]
  21. Gregory, A.; Williamson, E.; Prior, J.; Butcher, W.; Thompson, I.; Shaw, A.; Titball, R. Conjugation of Y. pestis F1-antigen to gold nanoparticles improves immunogenicity. Vaccine 2012, 30, 6777–6782. [Google Scholar] [CrossRef] [Green Version]
  22. Barhate, G.A.; Gaikwad, S.M.; Jadhav, S.S.; Pokharkar, V.B. Structure function attributes of gold nanoparticle vaccine asso-ciation: Effect of particle size and association temperature. Int. J. Pharm. 2014, 471, 439–448. [Google Scholar] [CrossRef] [PubMed]
  23. Dakterzada, F.; Mobarez, A.M.; Roudkenar, M.H.; Mohsenifar, A. Induction of humoral immune response against Pseudomonas aeruginosa flagellin(1-161) using gold nanoparticles as an adjuvant. Vaccine 2016, 34, 1472–1479. [Google Scholar] [CrossRef] [PubMed]
  24. Rio, E.R.-D.; Marradi, M.; González, R.C.; Cabanes, E.F.; Penadés, S.; Petrovsky, N.; Alvarez-Dominguez, C. A gold gly-co-nanoparticle carrying a listeriolysin O peptide and formulated with Advax™ delta inulin adjuvant induces robust T-cell protection against listeria infection. Vaccine 2015, 33, 1465–1473. [Google Scholar] [CrossRef] [Green Version]
  25. Safari, D.; Marradi, M.; Chiodo, F.; Th Dekker, H.A.; Shan, Y.; Adamo, R.; Oscarson, S.; Rijkers, G.T.; Lahmann, M.; Kamerling, J.P.; et al. Gold nanoparticles as carriers for a synthetic Streptococcus pneumoniae type 14 conjugate vaccine. Nanomedicine 2012, 7, 651–662. [Google Scholar] [PubMed]
  26. Gregory, A.; Judy, B.M.; Qazi, O.; Blumentritt, C.A.; Brown, K.A.; Shaw, A.; Torres, A.G.; Titball, R.W. A gold nanoparti-cle-linked glycoconjugate vaccine against Burkholderia mallei. Nanomed. Nanotechnol. Biol. Med. 2014, 11, 447–456. [Google Scholar] [CrossRef] [Green Version]
  27. Torres, A.G.; Gregory, A.; Hatcher, C.L.; Vinet-Oliphant, H.; Morici, L.A.; Titball, R.W.; Roy, C.J. Protection of non-human primates against glanders with a gold nanoparticle glycoconjugate vaccine. Vaccine 2014, 33, 686–692. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  28. Manea, F.; Bindoli, C.; Fallarini, S.; Lombardi, G.; Polito, L.; Lay, L.; Bonomi, R.; Mancin, F.; Scrimin, P. Multivalent, Sac-cha-ride-Functionalized Gold Nanoparticles as Fully Synthetic Analogs of Type A Neisseria meningitidis Antigens. Adv. Mater. 2008, 20, 4348–4352. [Google Scholar]
  29. Khlebtsov, N.; Bogatyrev, V.; Dykman, L.; Khlebtsov, B.; Staroverov, S.; Shirokov, A.; Matora, L.; Khanadeev, V.; Pylaev, T.; Tsyganova, N.; et al. Analytical and Theranostic Applications of Gold Nanoparticles and Multifunctional Nanocomposites. Theranostics 2013, 3, 167–180. [Google Scholar]
  30. Staroverov, S.A.; Dykman, L.A. Use of gold nanoparticles for the preparation of antibodies to tuberculin, the immunoassay of mycobacteria, and animal vaccination. Nanotechnol. Russ. 2013, 8, 816–822. [Google Scholar]
  31. Parween, S.; Gupta, P.K.; Chauhan, V.S. Induction of humoral immune response against PfMSP-119 and PvMSP-119 using gold nanoparticles along with alum. Vaccine 2011, 29, 2451–2460. [Google Scholar] [CrossRef]
  32. Kumar, R.; Ray, P.C.; Datta, D.; Bansal, G.P.; Angov, E.; Kumar, N. Nanovaccines for malaria using Plasmodium falciparum antigen Pfs25 attached gold nanoparticles. Vaccine 2015, 33, 5064–5071. [Google Scholar] [CrossRef] [Green Version]
  33. Lee, J.-H.; Choi, J.-W. Application of Plasmonic Gold Nanoparticle for Drug Delivery System. Curr. Drug Targets 2018, 19, 271–278. [Google Scholar] [CrossRef] [PubMed]
  34. Kalishwaralal, K.; Luboshits, G.; Firer, M.A. Synthesis of Gold Nanoparticle: Peptide-Drug Conjugates for Targeted Drug Delivery. Methods Mol. Biol. 2019, 2059, 145–154. [Google Scholar] [CrossRef]
  35. Liu, Y.; Crawford, B.M.; Vo-Dinh, T. Gold nanoparticles-mediated photothermal therapy and immunotherapy. Immunotherapy 2018, 10, 1175–1188. [Google Scholar] [CrossRef] [PubMed]
  36. Tao, C. Antimicrobial activity and toxicity of gold nanoparticles: Research progress, challenges and prospects. Lett. Appl. Microbiol. 2018, 67, 537–543. [Google Scholar] [CrossRef]
  37. Carabineiro, S.A.C. Applications of Gold Nanoparticles in Nanomedicine: Recent Advances in Vaccines. Molecules 2017, 22, 857. [Google Scholar]
  38. Fan, J.; Cheng, Y.; Sun, M. Functionalized Gold Nanoparticles: Synthesis, Properties and Biomedical Applications. Chem. Rec. 2020, 20, 1474–1504. [Google Scholar] [CrossRef]
  39. Cao-Milán, R.; Liz-Marzán, L.M. Gold nanoparticle conjugates: Recent advances toward clinical applications. Expert Opin. Drug Deliv. 2014, 11, 741–752. [Google Scholar] [CrossRef]
  40. Kohout, C.; Santi, C.; Polito, L. Anisotropic Gold Nanoparticles in Biomedical Applications. Int. J. Mol. Sci. 2018, 19, 3385. [Google Scholar] [CrossRef] [Green Version]
  41. Benne, N.; van Duijn, J.; Kuiper, J.; Jiskoot, W.; Slütter, B. Orchestrating immune responses: How size, shape and rigidity affect the immunogenicity of particulate vaccines. J. Control. Release 2016, 234, 124–134. [Google Scholar] [CrossRef]
  42. Carnovale, C.; Bryant, G.; Shukla, R.; Bansal, V. Identifying Trends in Gold Nanoparticle Toxicity and Uptake: Size, Shape, Capping Ligand, and Biological Corona. ACS Omega 2019, 4, 242–256. [Google Scholar] [CrossRef] [Green Version]
  43. Fan, Y.; Moon, J.J. Particulate delivery systems for vaccination against bioterrorism agents and emerging infectious pathogens. Wiley Interdiscip Rev. Nanomed. Nanobiotechnol. 2017, 9, e1403. [Google Scholar]
  44. Neto, L.M.M.; Kipnis, A.; Junqueira-Kipnis, A.P. Role of metallic nanoparticles in vaccinology: Implications for infectious disease vaccine development. Front. Immunol. 2017, 8, 239. [Google Scholar]
  45. Pati, R.; Shevtsov, M.; Sonawane, A. Nanoparticle Vaccines Against Infectious Diseases. Front. Immunol. 2018, 9, 2224. [Google Scholar] [PubMed] [Green Version]
  46. Blecher, K.; Nasir, A.; Friedman, A. The growing role of nanotechnology in combating infectious disease. Virulence 2011, 2, 395–401. [Google Scholar]
  47. Lopes, T.S.; Alves, G.G.; Pereira, M.R.; Granjeiro, J.M.; Leite, P.E.C. Advances and potential application of gold nanoparticles in nanomedicine. J. Cell. Biochem. 2019, 120, 16370–16378. [Google Scholar] [CrossRef]
  48. Wang, W.; Wang, J.; Ding, Y. Gold nanoparticle-conjugated nanomedicine: Design, construction, and structure–efficacy re-lationship studies. J. Mater. Chem. B 2020, 8, 4813–4830. [Google Scholar] [CrossRef]
  49. Ahmad, S.; Zamry, A.A.; Tan, H.-T.T.; Wong, K.K.; Lim, J.; Mohamud, R. Targeting dendritic cells through gold nanoparticles: A review on the cellular uptake and subsequent immunological properties. Mol. Immunol. 2017, 91, 123–133. [Google Scholar] [CrossRef]
  50. Yang, R.; Xu, J.; Xu, L.; Sun, X.; Chen, Q.; Zhao, Y.; Peng, R.; Liu, Z. Cancer Cell Membrane-Coated Adjuvant Nanoparticles with Mannose Modification for Effective Anticancer Vaccination. ACS Nano 2018, 12, 5121–5129. [Google Scholar] [CrossRef]
  51. Stead, S.O.; Kireta, S.; McInnes, S.J.P.; Kette, F.D.; Sivanathan, K.N.; Kim, J.; Cueto-Diaz, E.J.; Cunin, F.; Durand, J.-O.; Drogemuller, C.J.; et al. Murine and Non-Human Primate Dendritic Cell Targeting Nanoparticles for in Vivo Generation of Regulatory T-Cells. ACS Nano 2018, 12, 6637–6647. [Google Scholar]
  52. Shi, G.-N.; Zhang, C.-N.; Xu, R.; Niu, J.-F.; Song, H.-J.; Zhang, X.-Y.; Wang, W.-W.; Wang, Y.-M.; Li, C.; Wei, X.-Q.; et al. Enhanced antitumor immunity by targeting dendritic cells with tumor cell lysate-loaded chitosan nanoparticles vaccine. Biomaterials 2017, 113, 191–202. [Google Scholar]
  53. Yang, M.; Ding, J.; Zhang, Y.; Chang, F.; Wang, J.; Gao, Z.; Zhuang, X.; Chen, X. Activated macrophage-targeted dex-tran-methotrexate/folate conjugate prevents deterioration of collagen-induced arthritis in mice. J. Mater. Chem. B 2016, 4, 2102–2113. [Google Scholar] [PubMed]
  54. Heo, R.; Park, J.-S.; Jang, H.J.; Kim, S.-H.; Shin, J.M.; Suh, Y.D.; Jeong, J.H.; Jo, D.-G.; Park, J.H. Hyaluronan nanoparticles bearing γ-secretase inhibitor: In vivo therapeutic effects on rheumatoid arthritis. J. Control. Release 2014, 192, 295–300. [Google Scholar] [CrossRef] [PubMed]
  55. Yang, M.; Ding, J.; Feng, X.; Chang, F.; Wang, Y.; Gao, Z.; Zhuang, X.; Chen, X. Scavenger Receptor-Mediated Targeted Treatment of Collagen-Induced Arthritis by Dextran Sulfate-Methotrexate Prodrug. Theranostics 2017, 7, 97–105. [Google Scholar] [CrossRef] [PubMed]
  56. Versiani, A.F.; Andrade, L.M.; Martins, E.M.; Scalzo, S.; Geraldo, J.M.; Chaves, C.R.; Ferreira, D.C.; Ladeira, M.; Guatimosim, S.; Ladeira, L.O.; et al. Gold nanoparticles and their applications in biomedicine. Futur. Virol. 2016, 11, 293–309. [Google Scholar]
  57. Faa, G.; Gerosa, C.; Fanni, D.; Lachowicz, J.; Nurchi, V. Gold-Old Drug with New Potentials. Curr. Med. Chem. 2018, 25, 75–84. [Google Scholar] [CrossRef]
  58. Amina, S.J.; Guo, B. A Review on the Synthesis and Functionalization of Gold Nanoparticles as a Drug Delivery Vehicle. Int. J. Nanomed. 2020, 15, 9823–9857. [Google Scholar] [CrossRef]
  59. Tao, Y.; Zhang, Y.; Ju, E.G.; Ren, H.; Ren, J.S. Gold nanocluster-based vaccines for dual-delivery of antigens and im-munostimulatory oligonucleotides. Nanoscale 2015, 7, 12419–12426. [Google Scholar]
  60. Wang, Y.; Wang, Y.; Kang, N.; Liu, Y.; Shan, W.; Bi, S.; Ren, L.; Zhuang, G. Construction and Immunological Evaluation of CpG-Au@HBc Virus-Like Nanoparticles as a Potential Vaccine. Nanoscale Res. Lett. 2016, 11, 1–9. [Google Scholar] [CrossRef] [Green Version]
  61. Dykman, L.A. Gold nanoparticles for preparation of antibodies and vaccines against infectious diseases. Expert Rev. Vaccines 2020, 19, 465–477. [Google Scholar] [CrossRef] [Green Version]
  62. Sekimukai, H.; Iwata-Yoshikawa, N.; Fukushi, S.; Tani, H.; Kataoka, M.; Suzuki, T.; Hasegawa, H.; Niikura, K.; Arai, K.; Nagata, N. Gold nanoparticle-adjuvanted S protein induces a strong antigen-specific IgG response against severe acute res-piratory syndrome-related coronavirus infection, but fails to induce protective antibodies and limit eosinophilic infiltration in lungs. Microbiol. Immunol. 2019, 64, 33–51. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  63. Sonavane, G.; Tomoda, K.; Makino, K. Biodistribution of colloidal gold nanoparticles after intravenous administration: Effect of particle size. Colloids Surf. B Biointerfaces 2008, 66, 274–280. [Google Scholar] [PubMed]
  64. Van Haute, D.; Berlin, J.M. Challenges in realizing selectivity for nanoparticle biodistribution and clearance: Lessons from gold nanoparticles. Ther. Deliv. 2017, 8, 763–774. [Google Scholar] [CrossRef]
  65. Zhang, Y.; Liu, A.T.; Cornejo, Y.R.; Van Haute, D.; Berlin, J.M. A Systematic comparison of in vitro cell uptake and in vivo biodistribution for three classes of gold nanoparticles with saturated PEG coatings. PLoS ONE 2020, 15, e0234916. [Google Scholar] [CrossRef]
  66. Sykes, E.A.; Chen, J.; Zheng, G.; Chan, W.C. Investigating the Impact of Nanoparticle Size on Active and Passive Tumor Targeting Efficiency. ACS Nano 2014, 8, 5696–5706. [Google Scholar] [PubMed]
  67. Perrault, S.D.; Walkey, C.; Jennings, T.; Fischer, H.C.; Chan, W.C.W. Mediating Tumor Targeting Efficiency of Nanoparticles Through Design. Nano Lett. 2009, 9, 1909–1915. [Google Scholar]
  68. Blanco, E.; Shen, H.; Ferrari, M. Principles of nanoparticle design for overcoming biological barriers to drug delivery. Nat. Biotechnol. 2015, 33, 941–951. [Google Scholar]
  69. Monopoli, M.P.; Åberg, C.; Salvati, A.; Dawson, K.A. Biomolecular coronas provide the biological identity of nanosized materials. Nat. Nanotechnol. 2012, 7, 779–786. [Google Scholar] [CrossRef]
  70. Bertoli, F.; Garry, D.; Monopoli, M.P.; Salvati, A.; Dawson, K.A. The Intracellular Destiny of the Protein Corona: A Study on its Cellular Internalization and Evolution. ACS Nano 2016, 10, 10471–10479. [Google Scholar] [CrossRef]
  71. Cai, F.; Li, S.; Huang, H.; Iqbal, J.; Wang, C.; Jiang, X. Green synthesis of gold nanoparticles for immune response regulation: Mechanisms, applications, and perspectives. J. Biomed. Mater. Res. Part A 2021, 110, 424–442. [Google Scholar] [CrossRef]
  72. Niikura, K.; Matsunaga, T.; Suzuki, T.; Kobayashi, S.; Yamaguchi, H.; Orba, Y.; Kawaguchi, A.; Hasegawa, H.; Kajino, K.; Ninomiya, T.; et al. Gold Nanoparticles as a Vaccine Platform: Influence of Size and Shape on Immunological Responses in Vitro and in Vivo. ACS Nano 2013, 7, 3926–3938. [Google Scholar] [CrossRef] [PubMed]
  73. Nicol, J.R.; Dixon, D.; Coulter, J.A. Gold nanoparticle surface functionalization: A necessary requirement in the development of novel nanotherapeutics. Nanomedicine 2015, 10, 1315–1326. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  74. Farfán-Castro, S.; García-Soto, M.J.; Comas-García, M.; Arévalo-Villalobos, J.I.; Palestino, G.; González-Ortega, O.; Rosales-Mendoza, S. Synthesis and immunogenicity assessment of a gold nanoparticle conjugate for the delivery of a peptide from SARS-CoV-2. Nanomedicine 2021, 34, 102372. [Google Scholar] [CrossRef] [PubMed]
  75. Mulens-Arias, V.; Balfourier, A.; Nicolás-Boluda, A.; Carn, F.; Gazeau, F. Endocytosis-driven gold nanoparticle fractal rear-rangement in cells and its influence on photothermal conversion. Nanoscale 2020, 12, 21832–21849. [Google Scholar] [CrossRef]
  76. Dreaden, E.C.; Austin, L.A.; Mackey, M.A.; El-Sayed, M.A. Size matters: Gold nanoparticles in targeted cancer drug delivery. Ther. Deliv. 2012, 3, 457–478. [Google Scholar] [CrossRef] [Green Version]
  77. Cunha-Matos, C.A.; Millington, O.R.; Wark, A.W.; Zagnoni, M. Real-time assessment of nanoparticle-mediated antigen de-livery and cell response. Lab Chip 2016, 16, 3374–3381. [Google Scholar] [CrossRef] [Green Version]
  78. Bahamonde, J.; Brenseke, B.; Chan, M.; Kent, R.D.; Vikesland, P.J.; Prater, M.R. Gold Nanoparticle Toxicity in Mice and Rats: Species Differences. Toxicol. Pathol. 2018, 46, 431–443. [Google Scholar] [CrossRef]
  79. Deville, S.; Baré, B.; Piella, J.; Tirez, K.; Hoet, P.; Monopoli, M.P.; Dawson, K.A.; Puntes, V.; Nelissen, I. Interaction of gold nanoparticles and nickel(II) sulfate affects dendritic cell maturation. Nanotoxicology 2016, 10, 1395–1403. [Google Scholar] [CrossRef]
  80. El-Sayed, N.; Korotchenko, E.; Scheiblhofer, S.; Weiss, R.; Schneider, M. Functionalized multifunctional nanovaccine for targeting dendritic cells and modulation of immune response. Int. J. Pharm. 2020, 593, 120123. [Google Scholar] [CrossRef]
  81. Staroverov, S.A.; Volkov, A.A.; Mezhennyj, P.; Domnitsky, I.Y.; Fomin, A.S.; Kozlov, S.V.; Dykman, L.A.; Guliy, O.I. Pro-spects for the use of spherical gold nanoparticles in immunization. Appl. Microbiol. Biotechnol. 2018, 103, 437–447. [Google Scholar]
  82. Fytianos, K.; Rodriguez-Lorenzo, L.; Clift, M.J.; Blank, F.; Vanhecke, D.; von Garnier, C.; Petri-Fink, A.; Rothen-Rutishauser, B. Uptake efficiency of surface modified gold nanoparticles does not correlate with functional changes and cytokine secretion in human dendritic cells in vitro. Nanomed. Nanotechnol. Biol. Med. 2015, 11, 633–644. [Google Scholar]
  83. Wang, L.; Zhang, H.; Sun, L.; Gao, W.; Xiong, Y.; Ma, A.; Liu, X.; Shen, L.; Li, Q.; Yang, H. Manipulation of macrophage polarization by peptide-coated gold nanoparticles and its protective effects on acute lung injury. J. Nanobiotechnology 2020, 18, 1–16. [Google Scholar] [CrossRef] [Green Version]
  84. Luan, Y.; Van Der Mei, H.C.; Dijk, M.; Geertsema-Doornbusch, G.I.; Atema-Smit, J.; Ren, Y.; Chen, H.; Busscher, H.J. Po-larization of Macrophages, Cellular Adhesion, and Spreading on Bacterially Contaminated Gold Nanoparticle-Coatings in Vitro. ACS Biomater. Sci. Eng. 2020, 6, 933–945. [Google Scholar] [CrossRef] [Green Version]
  85. Tyner, K.; Bancos, S.; Stevens, D. Effect of silica and gold nanoparticles on macrophage proliferation, activation markers, cytokine production, and phagocytosis in vitro. Int. J. Nanomed. 2014, 10, 183–206. [Google Scholar] [CrossRef] [Green Version]
  86. Kingston, M.; Pfau, J.C.; Gilmer, J.; Brey, R. Selective inhibitory effects of 50-nm gold nanoparticles on mouse macrophage and spleen cells. J. Immunotoxicol. 2015, 13, 198–208. [Google Scholar] [CrossRef] [Green Version]
  87. Jiao, P.; Otto, M.; Geng, Q.; Li, C.; Li, F.; Butch, E.R.; Snyder, S.E.; Zhou, H.; Yan, B. Enhancing both CT imaging and natural killer cell-mediated cancer cell killing by a GD2-targeting nanoconstruct. J. Mater. Chem. B 2015, 4, 513–520. [Google Scholar]
  88. Qu, Y.; Li, Y.; Liao, S.; Sun, J.; Li, M.; Wang, D.; Xia, C.; Luo, Q.; Hu, J.; Luo, K.; et al. Linear and Core-Crosslinked Glyco-polymer-Gadolinium Conjugates: Preparation and Their Behaviors as Nanoscale Magnetic Resonance Imaging Contrast Agents. J. Biomed. Nanotechnol. 2019, 15, 1637–1653. [Google Scholar] [CrossRef] [PubMed]
  89. Elbagory, A.M.; Hussein, A.A.; Meyer, M. The In Vitro Immunomodulatory Effects of Gold Nanoparticles Synthesized from Hypoxis hemerocallidea Aqueous Extract and Hypoxoside on Macrophage and Natural Killer Cells. Int. J. Nanomed. 2019, 14, 9007–9018. [Google Scholar] [CrossRef] [Green Version]
  90. Abia, I.; Peng, T.Y.; Mains, S.; Pohl, N. Design and synthesis of thiol-terminated oligosaccharides for attachment on gold nanoparticles: Toward the development of an HIV vaccine. Abstr. Pap. Am. Chem. Soc. 2013, 246, 1155. [Google Scholar]
  91. Chiodo, F.; Enriquez-Navas, P.M.; Angulo, J.; Marradi, M.; Penades, S. Assembling different antennas of the gp120 high mannose-type glycans on gold nanoparticles provides superior binding to the anti-HIV antibody 2G12 than the individual antennas. Carbohydr. Res. 2015, 405, 102–109. [Google Scholar]
  92. Xu, L.; Liu, Y.; Chen, Z.; Li, W.; Liu, Y.; Wang, L.; Liu, Y.; Wu, X.; Ji, Y.; Zhao, Y.; et al. Surface-Engineered Gold Nanorods: Promising DNA Vaccine Adjuvant for HIV-1 Treatment. Nano Lett. 2012, 12, 2003–2012. [Google Scholar] [PubMed]
  93. Di Gianvincenzo, P.; Calvo, J.; Perez, S.; Álvarez, A.; Bedoya, L.M.; Alcamí, J.; Penadés, S. Negatively charged glyco-nanoparticles modulate and stabilize the secondary structures of a gp120 V3 loop peptide: Toward fully synthetic HIV vaccine candidates. Bioconjug Chem. 2015, 26, 755–765. [Google Scholar]
  94. Negahdari, B.; Darvishi, M.; Saeedi, A.A. Gold nanoparticles and hepatitis B virus. Artif. Cells Nanomed. Biotechnol. 2019, 47, 455–461. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  95. Zhang, L.; Widera, G.; Rabussay, D. Enhancement of the effectiveness of electroporation-augmented cutaneous DNA vaccination by a particulate adjuvant. Bioelectrochemistry 2004, 63, 369–373. [Google Scholar] [PubMed]
  96. Yavuz, E.; Bagriacik, E.U. Gold-based nano-adjuvants. In Proceedings of the IEEE 7th International Conference on Nanomaterials: Applications and Properties, Odesa, Ukraine, 10–15 September 2017. [Google Scholar]
  97. Kim, J.; Oh, S.Y.; Shukla, S.; Hong, S.B.; Heo, N.S.; Bajpai, V.; Chun, H.S.; Jo, C.-H.; Choi, B.G.; Huh, Y.S.; et al. Het-eroassembled gold nanoparticles with sandwich-immunoassay LSPR chip format for rapid and sensitive detection of hepatitis B virus surface antigen (HBsAg). Biosens. Bioelectron. 2018, 107, 118–122. [Google Scholar] [CrossRef] [PubMed]
  98. Shevtsov, M.; Zhao, L.; Protzer, U.; Van De Klundert, M.A.A. Applicability of Metal Nanoparticles in the Detection and Monitoring of Hepatitis B Virus Infection. Viruses 2017, 9, 193. [Google Scholar] [CrossRef] [Green Version]
  99. Draz, M.S.; Wang, Y.J.; Chen, F.F.; Xu, Y.H.; Shafiee, H. Electrically Oscillating Plasmonic Nanoparticles for Enhanced DNA Vaccination against Hepatitis C Virus. Adv. Funct. Mater. 2017, 27, 1604139. [Google Scholar]
  100. Li, Y.; Jin, Q.; Ding, P.; Zhou, W.; Chai, Y.; Li, X.; Wang, Y.; Zhang, G.-P. Gold nanoparticles enhance immune responses in mice against recombinant classical swine fever virus E2 protein. Biotechnol. Lett. 2020, 42, 1169–1180. [Google Scholar] [CrossRef]
  101. Paul, A.; Shi, Y.; Acharya, D.; Douglas, J.R.; Cooley, A.; Anderson, J.F.; Huang, F.; Bai, F. Delivery of antiviral small interfering RNA with gold nanoparticles inhibits dengue virus infection in vitro. J. Gen. Virol. 2014, 95, 1712–1722. [Google Scholar] [CrossRef] [Green Version]
  102. Tao, W.; Hurst, B.L.; Shakya, A.K.; Uddin, J.; Ingrole, R.S.; Hernandez-Sanabria, M.; Arya, R.; Bimler, L.; Paust, S.; Tarbet, B.; et al. Consensus M2e peptide conjugated to gold nanoparticles confers protection against H1N1, H3N2 and H5N1 influenza A viruses. Antivir. Res. 2017, 141, 62–72. [Google Scholar] [CrossRef] [Green Version]
  103. Tao, W.; Gill, H.S. M2e-immobilized gold nanoparticles as influenza A vaccine: Role of soluble M2e and longevity of protection. Vaccine 2015, 33, 2307–2315. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  104. Tao, W.; Ziemer, K.S.; Gill, H.S. Gold nanoparticle–M2e conjugate coformulated with CpG induces protective immunity against influenza A virus. Nanomedicine 2014, 9, 237–251. [Google Scholar] [CrossRef] [PubMed] [Green Version]
  105. Bimler, L.; Song, A.Y.; Le, D.T.; Schafer, A.M.; Paust, S. GnP-M2e + sCpG vaccination of juvenile mice generates lifelong protective immunity to influenza a virus infection. Immun. Ageing 2019, 16, 23. [Google Scholar] [PubMed] [Green Version]
  106. Mezhenny, P.V.; Staroverov, S.A.; Volkov, A.A.; Kozlov, S.V.; Laskavy, V.N.; Dykman, L.A.; Isayeva, A.Y. Con-struction of conjugates of colloidal selenium and colloidal gold with the protein of influenza virus and the study of their im-munogenic properties. Bull Saratov State Agrar. Univ. 2013, 2, 29–32. [Google Scholar]
  107. Wang, C.; Zhu, W.; Wang, B.-Z. Dual-linker gold nanoparticles as adjuvanting carriers for multivalent display of re-combinant influenza hemagglutinin trimers and flagellin improve the immunological responses in vivo and in vitro. Int. J. Nanomed. 2017, 12, 4747–4762. [Google Scholar] [CrossRef] [Green Version]
  108. Wang, C.; Zhu, W.; Luo, Y.; Wang, B.-Z. Gold nanoparticles conjugating recombinant influenza hemagglutinin trimers and flagellin enhanced mucosal cellular immunity. Nanomed. Nanotechnol. Biol. Med. 2018, 14, 1349–1360. [Google Scholar] [CrossRef]
  109. Chen, H.-W.; Huang, C.-Y.; Lin, S.-Y.; Fang, Z.-S.; Hsu, C.-H.; Lin, J.-C.; Chen, Y.-I.; Yao, B.-Y.; Hu, C.-M.J. Synthetic virus-like particles prepared via protein corona formation enable effective vaccination in an avian model of coronavirus infection. Biomaterials 2016, 106, 111–118. [Google Scholar]
  110. Staroverov, S.A.; Vidyasheva, I.V.; Gabalov, K.P.; Vasilenko, O.A.; Laskavyi, V.N.; Dykman, L.A. Immunostimulatory effect of gold nanoparticles conjugated with transmissible gastroenteritis virus. Bull. Exp. Biol. Med. 2011, 151, 436–439. [Google Scholar]
  111. Stone, J.; Thornburg, N.J.; Blum, D.L.; Kuhn, S.J.; Wright, D.W.; Crowe, J.E. Gold nanorod vaccine for respiratory syncytial virus. Nanotechnology 2013, 24, 295102. [Google Scholar]
  112. Bawage, S.; Tiwari, P.M.; Singh, A.; Dixit, S.; Pillai, S.R.; Dennis, V.A.; Singh, S.R. Gold nanorods inhibit respiratory syncytial virus by stimulating the innate immune response. Nanomed. Nanotechnol. Biol. Med. 2016, 12, 2299–2310. [Google Scholar] [CrossRef] [Green Version]
  113. DeRussy, B.M.; Aylward, M.A.; Fan, Z.; Ray, P.C.; Tandon, R. Inhibition of cytomegalovirus infection and photo-thermolysis of infected cells using bioconjugated gold nanoparticles. Sci. Rep. 2014, 4, 5550. [Google Scholar] [PubMed]
  114. Ding, P.; Zhang, T.; Li, Y.; Teng, M.; Sun, Y.; Liu, X.; Chai, S.; Zhou, E.; Jin, Q.; Zhang, G. Nanoparticle orientationally displayed antigen epitopes improve neutralizing antibody level in a model of porcine circovirus type 2. Int. J. Nano Med. 2017, 12, 5239–5254. [Google Scholar]
  115. Dykman, L.A.; Volokh, O.A.; Kuznetsova, E.M.; Nikiforov, A.K. Immunogenicity of Conjugates of Protective Antigen Complexes of Tularemia Microbe with Gold Nanoparticles. Nanotechnol. Russ. 2018, 13, 384–392. [Google Scholar]
  116. Staroverov, S.A.; Ermilov, D.N.; Shcherbakov, A.A.; Semenov, S.V.; Shchegolev, S.I.; Dykman, L.A. Generation of antibodies to Yersinia pseudotuberculosis antigens using the colloid gold particles as an adjuvant. Zh Mikrobiol. Epidemiol. Immunobiol. 2003, 3, 54–57. [Google Scholar]
  117. Chowdhury, R.; Ilyas, H.; Ghosh, A.; Ali, H.; Ghorai, A.; Midya, A.; Jana, N.R.; Das, S.; Bhunia, A. Multivalent gold nanoparticle–peptide conjugates for targeting intracellular bacterial infections. Nanoscale 2017, 9, 14074–14093. [Google Scholar] [CrossRef]
  118. Fallarini, S.; Paoletti, T.; Battaglini, C.O.; Ronchi, P.; Lay, L.; Bonomi, R.; Jha, S.; Mancin, F.; Scrimin, P.; Lombardi, G. Factors affecting T cell responses induced by fully synthetic glyco-gold-nanoparticles. Nanoscale 2012, 5, 390–400. [Google Scholar] [CrossRef] [Green Version]
  119. Calderón-Gonzalez, R.; Terán-Navarro, H.; Frande-Cabanes, E.; Ferrández-Fernández, E.; Freire, J.; Penadés, S.; Marradi, M.; García, I.; Gomez-Román, J.; Yañez-Díaz, S.; et al. Pregnancy Vaccination with Gold Glyco-Nanoparticles Car-rying Listeria monocytogenes Peptides Protects against Listeriosis and Brain- and Cutaneous-Associated Morbidities. Nanomaterials 2016, 6, 151. [Google Scholar]
  120. Vetro, M.; Safari, D.; Fallarini, S.; Salsabila, K.; Lahmann, M.; Penadés, S.; Lay, L.; Marradi, M.; Compostella, F. Preparation and immunogenicity of gold glyco-nanoparticles as antipneumococcal vaccine model. Nanomedicine 2017, 12, 13–23. [Google Scholar]
  121. Barhate, G.; Gautam, M.; Gairola, S.; Jadhav, S.; Pokharkar, V. Quillaja saponaria extract as mucosal adjuvant with chitosan functionalized gold nanoparticles for mucosal vaccine delivery: Stability and immunoefficiency studies. Int. J. Pharm. 2013, 441, 636–642. [Google Scholar]
  122. Barhate, G.; Gautam, M.; Gairola, S.; Jadhav, S.; Pokharkar, V. Enhanced mucosal immune responses against tetanus toxoid using novel delivery system comprised of chitosan-functionalized gold nanoparticles and botanical adjuvant: Charac-terization, immunogenicity, and stability assessment. J. Pharm. Sci. 2014, 103, 3448–3456. [Google Scholar]
  123. Liu, J.; Wang, J.; Li, Z.; Meng, H.; Zhang, L.; Wang, H.; Li, J.; Qu, L. A lateral flow assay for the determination of human tetanus antibody in whole blood by using gold nanoparticle labeled tetanus antigen. Mikrochim. Acta 2018, 185, 110. [Google Scholar] [CrossRef] [PubMed]
  124. Assis, N.R.; Caires, A.; Figueiredo, B.C.; Morais, S.B.; Mambelli, F.S.; Marinho, F.; Ladeira, L.O.; Oliveira, S.C. The use of gold nanorods as a new vaccine platform against schistosomiasis. J. Control. Release 2018, 275, 40–52. [Google Scholar] [PubMed]
  125. Shukla, R.; Bansal, V.; Chaudhary, M.; Basu, A.; Bhonde, R.R.; Sastry, M. Biocompatibility of gold nanoparticles and their endocytotic fate inside the cellular compartment: A microscopic overview. Langmuir 2005, 21, 10644–10654. [Google Scholar]
  126. Homberger, M.; Simon, U. On the application potential of gold nanoparticles in nanoelectronics and biomedicine. Philos. Trans. R. Soc. A Math. Phys. Eng. Sci. 2010, 368, 1405–1453. [Google Scholar]
  127. Glazer, E.S.; Zhu, C.; Hamir, A.N.; Borne, A.; Thompson, C.S.; Curley, S.A. Biodistribution and acute toxicity of naked gold nanoparticles in a rabbit hepatic tumor model. Nanotoxicology 2011, 5, 459–468. [Google Scholar]
  128. Li, J.J.; Hartono, D.; Ong, C.N.; Bay, B.H.; Yung, L.Y.L. Autophagy and oxidative stress associated with gold nano-particles. Biomaterials 2010, 31, 5996–6003. [Google Scholar] [PubMed]
  129. Ma, X.; Wu, Y.; Jin, S.; Tian, Y.; Zhang, X.; Zhao, Y.; Yu, L.; Liang, X.J. Gold nanoparticles induce autophagosome accumulation through size-dependent nanoparticle uptake and lysosome impairment. ACS Nano 2011, 5, 8629–8639. [Google Scholar]
  130. Wang, L.; Liu, Y.; Li, W.; Jiang, X.; Ji, Y.; Wu, X.; Xu, L.; Qiu, Y.; Zhao, K.; Wei, T.; et al. Selective Targeting of Gold Nanorods at the Mitochondria of Cancer Cells: Implications for Cancer Therapy. Nano Lett. 2011, 11, 772–780. [Google Scholar]
  131. Chang, M.-Y.; Shiau, A.-L.; Chen, Y.-H.; Chang, C.-J.; Chen, H.H.-W.; Wu, C.-L. Increased apoptotic potential and dose-enhancing effect of gold nanoparticles in combination with single-dose clinical electron beams on tumor-bearing mice. Cancer Sci. 2008, 99, 1479–1484. [Google Scholar]
  132. Singh, P.; Pandit, S.; Mokkapati, V.; Garg, A.; Ravikumar, V.; Mijakovic, I. Gold Nanoparticles in Diagnostics and Therapeutics for Human Cancer. Int. J. Mol. Sci. 2018, 19, 1979. [Google Scholar] [CrossRef]
  133. Weintraub, K. Biomedicine: The new gold standard. Nature 2013, 495, S14–S16. [Google Scholar] [CrossRef] [PubMed]
  134. Nel, A.; Xia, T.; Mädler, L.; Li, N. Toxic Potential of Materials at the Nanolevel. Science 2006, 311, 622–627. [Google Scholar] [PubMed] [Green Version]
  135. Rosa, S.; Connolly, C.; Schettino, G.; Butterworth, K.T.; Prise, K.M. Biological mechanisms of gold nanoparticle radio-sensitization. Cancer Nanotechnol. 2017, 8, 2. [Google Scholar] [PubMed] [Green Version]
  136. Havaki, S.; Kotsinas, A.; Chronopoulos, E.; Kletsas, D.; Georgakilas, A.; Gorgoulis, V.G. The role of oxidative DNA damage in radiation induced bystander effect. Cancer Lett. 2015, 356, 43–51. [Google Scholar] [PubMed]
  137. Khlebtsov, N.; Dykman, L. Biodistribution and toxicity of engineered gold nanoparticles: A review of in vitro and in vivo studies. Chem. Soc. Rev. 2011, 40, 1647–1671. [Google Scholar]
  138. Pan, Y.; Leifert, A.; Ruau, D.; Neuss, S.; Bornemann, J.; Schmid, G.; Brandau, W.; Simon, U.; Jahnen-Dechent, W. Gold Nanoparticles of Diameter 1.4 nm Trigger Necrosis by Oxidative Stress and Mitochondrial Damage. Small 2009, 5, 2067–2076. [Google Scholar]
  139. Katas, H.; Moden, N.Z.; Lim, C.S.; Celesistinus, T.; Chan, J.Y.; Ganasan PSuleman Ismail Abdalla, S. Biosynthesis and potential applications of silver and gold nanoparticles and their chitosan-based nanocomposites in nanomedicine. J. Nanotechnol. 2018, 2018, 4290705. [Google Scholar]
  140. De Freitas, L.F.; Varca, G.H.C.; Batista, J.G.D.S.; Lugão, A.B. An overview of the synthesis of gold nanoparticles using radiation technologies. Nanomaterials 2018, 8, 939. [Google Scholar]
  141. Chen, H.; Dorrigan, A.; Saad, S.; Hare, D.J.; Cortie, M.B.; Valenzuela, S.M. In vivo study of spherical gold nanoparticles: Inflammatory effects and distribution in mice. PLoS ONE 2013, 8, e58208. [Google Scholar]
  142. Murphy, C.J.; Gole, A.M.; Stone, J.W.; Sisco, P.N.; Alkilany, A.M.; Goldsmith, E.C.; Baxter, S.C. Gold nanoparticles in biology: Beyond toxicity to cellular imaging. Acc. Chem. Res. 2008, 41, 1721–1730. [Google Scholar]
Figure 1. Schematic representation of the gold nanoparticle and its possible uses in the biomedical field. The gold nanoparticle can be tagged with one or more things depending on its intended use, such as the delivery of nucleic acids or protein fragments or the delivery of drugs and their controlled release. Targeting of its contents to the specific cells of the body is performed by using antibody-tagged GNPs or by the use of ligands attached to them targeting specific receptors of the body. Imaging techniques have been immensely developed by the use of GNP-tagged dye optical probes.
Figure 1. Schematic representation of the gold nanoparticle and its possible uses in the biomedical field. The gold nanoparticle can be tagged with one or more things depending on its intended use, such as the delivery of nucleic acids or protein fragments or the delivery of drugs and their controlled release. Targeting of its contents to the specific cells of the body is performed by using antibody-tagged GNPs or by the use of ligands attached to them targeting specific receptors of the body. Imaging techniques have been immensely developed by the use of GNP-tagged dye optical probes.
Vaccines 10 00505 g001
Figure 2. A schematic representation of the use of GNPs in developing nanovaccines against a virus. (A) The protein subunit from the virus is isolated to determine the peptide sequence, which is both immunogenic for the host and conserved across multiple strains of the virus. The peptide is tagged with GNPs to create the novel nanovaccine and tested on the mice model. (B) The immune cells of the mice are triggered as the dendritic cells start presenting the peptides to the CD4 helper T cells and the CD8 cytotoxic T cells. The clonal expansion of the activated helper T cells and subsequent activation of the B cells into the plasma cells lead to the production of the antibodies specific to the peptide used for nanovaccine production. The cytotoxic T cells can recognize and deploy themselves in the killing of the infected cells. (C) The cytokines produced during the process of immune regulation of the nanovaccine produce a chemical milieu where the immune cells can favorably fight against the pathogens and shape the Th1 or Th2 immune response depending on the inflammation status. The antibodies can recognize the peptide sequence present in the whole virus and neutralize them effectively. (D) The B and T memory cells formed during this vaccination process can hold the information of the peptide used during the process and live long after. They are equipped to start an immediate immune response against any future challenge of the same virus and thus can eliminate them before they can cause major harm to the host.
Figure 2. A schematic representation of the use of GNPs in developing nanovaccines against a virus. (A) The protein subunit from the virus is isolated to determine the peptide sequence, which is both immunogenic for the host and conserved across multiple strains of the virus. The peptide is tagged with GNPs to create the novel nanovaccine and tested on the mice model. (B) The immune cells of the mice are triggered as the dendritic cells start presenting the peptides to the CD4 helper T cells and the CD8 cytotoxic T cells. The clonal expansion of the activated helper T cells and subsequent activation of the B cells into the plasma cells lead to the production of the antibodies specific to the peptide used for nanovaccine production. The cytotoxic T cells can recognize and deploy themselves in the killing of the infected cells. (C) The cytokines produced during the process of immune regulation of the nanovaccine produce a chemical milieu where the immune cells can favorably fight against the pathogens and shape the Th1 or Th2 immune response depending on the inflammation status. The antibodies can recognize the peptide sequence present in the whole virus and neutralize them effectively. (D) The B and T memory cells formed during this vaccination process can hold the information of the peptide used during the process and live long after. They are equipped to start an immediate immune response against any future challenge of the same virus and thus can eliminate them before they can cause major harm to the host.
Vaccines 10 00505 g002
Table 1. Use of GNP based nanovaccine against viral pathogens.
Table 1. Use of GNP based nanovaccine against viral pathogens.
SNAntigen Conjugated with AuNPGNP/AdjuvantImmunization MechanismImmune ResponseRef.
1Surface antigens spike glycoprotein of avian coronavirus Virus-like particles (VLP) by incubating the antigen with 100 nm AuNPsDose: Single, 10 μg
Mode: Intramuscularly
Animals: BALB/C mice and specific pathogen-free chickens
  • Showed increased antigen delivery to lymphoid organs.
  • An enhanced response of spleen T cells.
  • Higher antibody titers.
  • A reduction in symptoms of infection.(Comparative study with a commercial vaccine also showed that the AuNP conjugate provided better protection against the virus.)
[109]
2Surface antigens gastroenteritis virusConjugated with 15 nm AuNPsGuinea pigs twice subcutaneously with 125 μg, mice once intraperitoneally with 70 μg, and rabbits three times subcutaneously with 220 μg
  • Increased the level of IL-6, IFN-γ, IL-1β in the blood plasma.
  • Higher respiratory activity of peritoneal macrophages and spleen lymphocytes.
  • Activation of humoral immunity; increase in the number of follicles in the spleen.
[84,110]
3Glycoprotein antigen of respiratory syncytial virusNanorods Human cell treatment in vitroHuman dendritic cells induced an immune activation (proliferation and expansion) of primary T cells.[111]
4Glycoprotein isolated from fixed rabies virus, strain Moscow 3253Conjugated with 15 nm AuNPsAnimal: Mice
Mode: Intraperitoneally
Dose: 25 μg in four booster doses, 50 μg was used
Develop highly specific neutralizing antibodies against the virus.[112]
5Surface glycoprotein (gB) of human cytomegalovirus (CMV, a herpes virus) Conjugated with AuNPIn vitro
  • Viral replication blocked.
  • Virus-induced cytopathogenic effects blocked.
  • Virus spread in cell culture decreased without generating cytotoxicity.
  • Cells gained resistance to CMV infection post-treatment.
[113]
6West Nile fever virusMultiple sizes and shapes of AuNPs used:
20 and 40 nm nanospheres, 40 × 20 nm nanorods, and 40 × 40 × 40 nm nanocubes
Animal: Mice
Mode: Intraperitoneally
Dose: 100 μg
No. of doses: 2
  • 40 nm nanospheres induced the highest level of specific antibodies.
  • The dendritic cells and macrophages absorbed larger numbers of nanorods.
  • IL-1β and IL-18 synthesis increased while using nanorods, while nanospheres and nanocubes resulted in higher synthesis of TNFα, IL6, IL12, and granulocyte-macrophage colony-stimulating factor.
[72]
7Capsid (Cap) protein from pathogenic porcine circovirusConjugated with 23 nm GNPsIn vitro and mice immunized twice subcutaneously
  • Increase in Cap protein phagocytosis.
  • High production of virus-neutralizing antibodies.(Similar results were obtained with classical swine fever virus antigen.)
[114]
Table 2. Use of GNP based nanovaccine against bacterial pathogens.
Table 2. Use of GNP based nanovaccine against bacterial pathogens.
SNAntigen Conjugated with AuNPGNP/AdjuvantImmunization MechanismImmune ResponseRef.
1Listeriolysin O peptide (LLO91-99) from Listeria monocytogenesConjugated with AuNPA single intravenous or intraperitoneal immunization of mice
  • Increase in the number of splenic CD4+ and CD8+ T cells, NK cells, and CD8α+ dendritic cells specific T cell response.
  • An increase in the synthesis of the cytokines IL-12, TNF-α, IFN-γ, and MCP-1.
  • Newborn mice born to vaccinated females were healthy and bacteria-free.
[95,119]
2A synthetic tetrasaccharide epitope, similar to the capsular polysaccharide of Streptococcus pneumoniae type14Conjugated with 2 nm AuNP + T helper peptideAnimal: Mice
Dose: 3 μg
Mode: Intradermal
No. of doses: 1
  • Specific high-titer IgG.
  • Increase in the level of the cytokines IL-2, IL-4, IL-5, IL-17, and IFN-γ.
  • Increased phagocytosis of type 14 bacteria stimulated by antisaccharide antibodies.
[25,120]
3Bacterial vesicles of the outer membrane of Escherichia coliConjugated with 30 nm AuNPsInjected in mice three times subcutaneously
  • Rapid maturation and activation of dendritic cells in the lymph nodes.
  • Increase in higher avidity antibodies.
  • Enhancement of IFN-γ and IL-17, indicating strong Th1 and Th17 cellular responses.
[19]
4Tetanus toxoid Clostridium tetani Conjugated with 25 nm AuNPs + plant adjuvants (saponins) from Quillaja saponaria (79) and Asparagus racemosus (80)Subcutaneous injection, or transmucosal deliveryOral administration highly enhanced mucosal immune response in the presence of plant adjuvants.[121,122,123]
5Burkholderia mallei recombinant protein: Hc fragment of tetanus toxin, hemolysin (produced by both B. mallei and B. pseudomallei), and flagellin (produced by B. pseudomallei)15 nm AuNP functionalized with purified LPS from a nonvirulent B. thailandensis strainBALB/C mice, intranasal, 3 different dose concentrations
  • Generated significantly higher antibody titers compared with LPS alone.
  • Improved protection against a lethal inhalation challenge of B. mallei in the murine model of infection.
[26]
67.5 μg of tuberculin (mixture of the surface antigens of various types of mycobacteria)Conjugated with 15 nm AuNPsRabbits, four times intramuscularlyHigh antibody production against multiple types of mycobacteria.[29,30]
7Specific immunogenic antigens LomW and EscC from enterohemorrhagic strain E. coli O157: H7Conjugated with AuNPMice, three times subcutaneously, 2-week intervals
  • Higher-titer IgG and IgA.
  • Serum IgG titer increase correlates with the decrease in the intestinal colonization of E. coli.
  • Reduced the adhesion of E. coli O157: H7 and two different E. coli pathotypes to humans.
  • Bactericidal properties of intestinal epithelial cells specific to antigen generated.
[20]
Table 3. Use of GNP based nanovaccine against parasitic pathogens.
Table 3. Use of GNP based nanovaccine against parasitic pathogens.
SNAntigenAuNP/AdjuvantImmunization MechanismImmune ResponseRef.
1Recombinant protein from rSm2 Schistosoma mansoni Gold nanorods conjugatedMice immunization intraperitoneally with 2 μg dose
  • Th1 immunological response.
  • Higher production of IFN-γ, mostly by CD4+ and CD8+ T cells.
  • Activated dendritic cells (in vitro).
  • Increase in the expression of MHCI and MHCII and the synthesis of IL-1β.
[124]
2Surface protein Pfs25 from the P. falciparum Attached to various AuNPs, including nanospheres, nanostars, nanocages, and nanoprismsMice were immunized with the resulting conjugates.
Dose: 10 μg, three times, intramuscularly
  • High-titer antibodies.
  • The highest titers were obtained with gold nanospheres and nanostars.
  • The antibodies blocked the transmission of parasites to mosquitoes in membrane-feeding assays.
[32]
3C-terminal 19 kDa fragment of merozoite surface protein 1 from the malaria pathogen Plasmodium falciparum17 nm AuNP conjugated
+ adjuvant Alhydrogel®
Mice were immunized three times subcutaneously at a dose of 25 μg
  • Antibodies produced against the weakly immunogenic peptides.
  • It blocked the invasion of P. falciparum in an in vitro assay.
[31]
Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Share and Cite

MDPI and ACS Style

Sengupta, A.; Azharuddin, M.; Al-Otaibi, N.; Hinkula, J. Efficacy and Immune Response Elicited by Gold Nanoparticle- Based Nanovaccines against Infectious Diseases. Vaccines 2022, 10, 505. https://doi.org/10.3390/vaccines10040505

AMA Style

Sengupta A, Azharuddin M, Al-Otaibi N, Hinkula J. Efficacy and Immune Response Elicited by Gold Nanoparticle- Based Nanovaccines against Infectious Diseases. Vaccines. 2022; 10(4):505. https://doi.org/10.3390/vaccines10040505

Chicago/Turabian Style

Sengupta, Anirban, Mohammad Azharuddin, Noha Al-Otaibi, and Jorma Hinkula. 2022. "Efficacy and Immune Response Elicited by Gold Nanoparticle- Based Nanovaccines against Infectious Diseases" Vaccines 10, no. 4: 505. https://doi.org/10.3390/vaccines10040505

APA Style

Sengupta, A., Azharuddin, M., Al-Otaibi, N., & Hinkula, J. (2022). Efficacy and Immune Response Elicited by Gold Nanoparticle- Based Nanovaccines against Infectious Diseases. Vaccines, 10(4), 505. https://doi.org/10.3390/vaccines10040505

Note that from the first issue of 2016, this journal uses article numbers instead of page numbers. See further details here.

Article Metrics

Back to TopTop